Hydraulic shock absorber



July 21, 1936. w. J. SMITH HYDRAULIC SHOCK ABSORBER Fi1ed Sept. 11, 1935 wrm/mf? /4//7/@72 123:72#

Patented July 2l, 1936 trs Voire HYDRAULIC SHDCK ABSRBER William J. Smith, Philadelphia, Pa., assigner to `los. B. McCall, Jr., Philadelphia, Pa.

The object of my invention is to provide a hydraulic shock absorber of simplified and improved `construction. One feature of my invention consists in the provision of a reservoir for Ythe shock absorber liquid, said reservoir beinglocated above the acting shock absorber chamber, so that any froth or the like in the liquid is contained in the reservoir and does not get into the acting chamber.

Another feature of my invention is the provision of` means whereby the shock absorber can be readily assembled and disassembled without the use of special tools or without exact and intricate movements between the relative parts of the shock absorber.

Other features of my invention Will be readily app-arent from the annexed drawing and specication to .which reference to the details of my invention is made and at the end whereof the novel features of my invention will be specioally pointed cut and claimed.

In the drawing:

Fig.,1 is a longitudinal cross-section through ,I my device.

Fig. 2.is a longitudinal cross-section through Y one of the attaching means at right angles to Fig. 1.

Fig. 3 is aV transverse cross-section on line 3-3 of Fig. l.

Fig. 4 is a detail view in elevation of the bypass valve and the means for retaining it in position.

Fig. 5 is a transverse cross-section on line 5 5 of Fig. 1.

In that embodiment of my invention chosen for illustration and description, my device is shown as consisting of a cylindrical, tubular body I having one end 2 thereof closed and having a ring 3 attached to said closed end. Ring 3 serves to connect the shock absorber to one of the operating parts. On one outer surface,

body I has a bypass channel 4 to which access is had from the interior of the body by means of a passage 5, and from which exit is had through a passage 6. On its opposite side, body I carries a return passage for conduit I, to

which inlet is had through opening 8 and from which exit is had through passage 9. A filling plug I0 may be connected adjacent passage 9 or in any other convenient location.

Within body I and (1o-operating therewith, as with a cylinder, is mounted a piston II having a plurality of ports I2 extending therethrough. Within a portion of ports I2 are mounted square valves I3, whose smallest transverse dimensions are large enough to close the smaller diameters .of ports I2 but which are shorter than the therein a packing or bushing I8 providing a slid- 10V ing bearing for piston rod I5.

At`the` upper end of body I there is also provided a reservoir I9 in the shape of a cylindrical cup or chamber having at its upper end an outwardly extending-flange 20 adapted to be clamped 15 between the open end of body7 I and cap Il and to thereby retain vthe reservoir in position. Lower end of reservoir I9 is closed by a base through which piston rod I5 passes and through i which passports 2|, in which'are mounted ball- 20 valves 22 retained in place by pins 23 or like means. On its outer face, reservoir I9 carries an annular groove 24 suitably located so as to be aligned with exit passage 9. A plurality of ports 25 communicate from groove 29 with the 25 interior of reservoir I9. l

Bypass passage 4 is controlled by a bypass valve, shown in Fig. 4 as consisting of a body portion 26 having a passage 2l passing therethrough. At one or both ends thereof, passage 30 2'! has a tapering indentation 28 in the outer surface of body 26 or a so-called sneak. The bypass valve also has in its outer surface an annular groove 29, into which projects aV screw or like device 39 for retaining the bypass valve 35 on body I. Bypass valve 25 is adjusted by means of a slot 3l in its outer surface for receiving a screw-driver or like device.

The operation of my device is believed to be obvious. The parts are assembled in the position 40 shown and the device is filled with shock absorber liquid either before cap II is screwed into position or through filling plug I0. Shock absorber liquid should be contained in reservoir I9 above the level of ports 25. In use, the valves I3 and 22 are so 45 designed that, upon movement of piston I I in one direction, both of these valves are closed, thereby trapping liquid between piston II and the parts forming the cylinder surrounding the piston. This liquid is forced out through port 5 and by- 50 pass passage 4. The amount of the flow of liquid through bypass passage 4 is controlled by valve 26, since passage 21 is aligned with the axis of bypass passage li. If the passage 2l is turned into alignment with bypass passage 4, the full ow of Y of said piston in` a direction to open said first valve liquid can pass, but the bypass valve may be turned so that the indentations or sneaks Z8 partially overlie the adjacent portions of bypass passage i, so that ow of liquid through bypass passage is reduced or completely cut 01T. Upon movement of piston ll in the opposite direction, both valves i3 and 22 are open, and in addition, liquid can flow from the space between the outer face of piston Il and the closed end of body I through port 8, outlet 9, annular groove 24, and ports 25, to the interior of reservoir I9.

It is to be understood that my invention is not y to be limited save as the scope of the prior art and of the attached claims mayvrequire.

I clairnz- 1. An hydraulic shock absorber, comprisingin combination: a cylindrical, tubular body having a closed end and forming part of a cylinder; a-piston'mounted Within said cylinder for reciprocati movement 'of said piston in the opposite direction; a second valve in said' reservoir and controlling Y a passage leading from the space, which is between said cylinder and said piston and is adjacent to the reservoiniandleading to said reservoir and arranged so as to be opened upon movement and to be closed upon movement of said piston to close said first valve; a conduit leading from the space between said cylinder and said piston to the space between the outer face of said piston andthe closed endof said body; a bypass valve controlling the flow ofr shock absorber liquid through'saidlconduit thereby controlling the action of said shock absorber; and a second rconduit leading, from the space between the outer face of said piston and the closed end of said body to said reservoir. o i

2. An hydraulic shock absorber according to claim 1 in which the bypass valve consists of a cylindrical body having an opening extending transversely therethrough in alignment with the o axis of said second conduit and having a tapering indentation on 'the outer surface thereof connecting with one end of said opening, said bypass valve having an annular groove in its outer surgroove and retainingY said bypass valve against' axial movement. Y y Y t 3.7An hydraulic shock absorber according to groove in its outer surface in communication with one end ofrsaid second conduit and has a plurality of openings therein leadingl from said groove to the interior of said reservoir.

4. An hydraulic shock absorber, comprising in combination, a cylinder, a piston mounted for movement in said cylinder, a first valve in said piston arranged so as to be open upon movement, of said piston in one direction and to be closedV upon movement of said pistonVY inf the opDOSite direction, -a wall in said cylinder having `a passage therethrough and co-operating with'one end of said cylinder to form a reservoir for Ashock ab#V Y sorber liquid and cooperatingrwith said ,piston to form a pressurechamber within s aid cylinder' be# tween said piston and said walLa second valve controlling said passagein said wall which passage connects said reservoir and said Vpressure chamber, said second valve being arranged so asV Vdirection to opened said rst valve andvto be closed upon movement of said pistonin the direction to close said'rst valve, a conduit providing Vcommunication between said pressure chamber claim l in Vwhich said reservoir has an annular Y and said reservoir, a bypass valve controlling the y flow of'liquid through said conduit thereby regulating the .action vof said shock absorber, and a second conduit leading from the opposite side of said piston from said pressure chamber and from v Y said reservoir and leading to said reservoir. r

WILLIAM J.V SMITH.v 45:' 

